Option Type | Default Value | #pragma options | C | C++ |
-qoption | noonce | ONCE | x |
Syntax
-qonce | -qnoonce ONCE | NOONCE
Purpose
Avoids including a header file more than once even if it is specified in several of
the files you are compiling.
Notes
The compiler uses the full path name to determine if a file has already been
included. No attempt is made to resolve . or .. in the
path name. #include statements that include . or ..
in the path statements may cause the same file to be included more than once.
The #pragma options keyword ONCE may appear anywhere in your code. It can be turned on and off by specifying ONCE and NOONCE, respectively.
Important! |
Do not use the -qonce option if both of the following
conditions are true:
va_list must be defined twice to have any effect, and -qonce defeats this purpose. |
Example
The following example shows how the compiler resolves whether a file has already been
included.
#include <stdio.h> /* Found in /usr/include/stdio.h */ #include <stdio.h> /* Already included */ #include </usr/include/stdio.h> /* Already included */ #include <./stdio.h> /* Resolves to /usr/include/./stdio.h */ /* which is the same file, but this */ /* file will be included again. */
List of Batch Compiler Options and Their Defaults
Equivalent Batch Compile-Link and Incremental
Build Options